安卓[android] 通过Uri获取File文件

/**
	 * 通过Uri返回File文件
	 * 注意：通过相机的是类似content://media/external/images/media/97596
	 * 通过相册选择的：file:///storage/sdcard0/DCIM/Camera/IMG_20150423_161955.jpg
	 * 通过查询获取实际的地址
	 * @param uri
	 * @return
	 */
	public File getFileByUri(Uri uri) {
		String path = null;
		if ("file".equals(uri.getScheme())) {
			path = uri.getEncodedPath();
			if (path != null) {
				path = Uri.decode(path);
				ContentResolver cr = activity.getContentResolver();
				StringBuffer buff = new StringBuffer();
				buff.append("(").append(Images.ImageColumns.DATA).append("=").append("'" + path + "'").append(")");
				Cursor cur = cr.query(Images.Media.EXTERNAL_CONTENT_URI, new String[] { Images.ImageColumns._ID, Images.ImageColumns.DATA }, buff.toString(), null, null);
				int index = 0;
				int dataIdx = 0;
				for (cur.moveToFirst(); !cur.isAfterLast(); cur.moveToNext()) {
					index = cur.getColumnIndex(Images.ImageColumns._ID);
					index = cur.getInt(index);
					dataIdx = cur.getColumnIndex(Images.ImageColumns.DATA);
					path = cur.getString(dataIdx);
				}
				cur.close();
				if (index == 0) {
				} else {
					Uri u = Uri.parse("content://media/external/images/media/" + index);
					System.out.println("temp uri is :" + u);
				}
			}
			if (path != null) {
				return new File(path);
			}
		} else if ("content".equals(uri.getScheme())) {
			// 4.2.2以后
			String[] proj = { MediaStore.Images.Media.DATA };
			Cursor cursor = activity.getContentResolver().query(uri, proj, null, null, null);
			if (cursor.moveToFirst()) {
				int columnIndex = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
				path = cursor.getString(columnIndex);
			}
			cursor.close();

			return new File(path);
		} else {
			Log.i(TAG, "Uri Scheme:" + uri.getScheme());
		}
		return null;
	}